Emerging and investigational drugs for premature ejaculation

Mechanism of Shugan Yidan fan, a Chinese herbal formula, in rat model of premature ejaculation

BACKGROUND

Premature ejaculation (PE) is one of the most common forms of sexual dysfunction in men, and multimodal therapeutic regimens should be considered to treat the condition. We developed a Chinese medicine herbal medicine, Shugan Yidan fang that had a significant clinical effect on PE patients, extending the time between penetration and ejaculation. However, the mechanism of this formula remains unclear. There is evidence that PE is associated with peripheral neuropathology, and the actions of dopamine (DA) and 5-hydroxytryptamine (5-HT). The aim of this study was to investigate the mechanism of Shugan Yidan fang's effect on PE through the relationship between sexual behavioristics and the level of neurotransmitters and dopamine receptors (DARs).

RESULTS

We showed that the male PE groups had a significant PE phenotype compared to healthy rats. Treatment with Shugan Yidan fang improved the behavioristics of the PE rats, and reduced the expression of DAR mRNA and protein while improving dopamine transporter levels.

CONCLUSIONS

Our study provided evidence for the beneficial effect of Shugan Yidan fang in PE therapy, and proposed a preliminary potential mechanism for the clinical application of the formula.

[Recommendations for the treatment of premature ejaculation]

OBJECTIVES

The Post-University Interdisciplinary Association of Sexology (AIUS) has brought together a panel of experts to develop French recommendations for the management of premature ejaculation.

METHODS

Systematic review of the literature between 01/1995 and 02/2022. Use of the clinical practice guidelines (CPR) method.

RESULTS

We recommend giving all patients with PE psychosexological counseling, and whenever possible combining pharmacotherapies and sexually-focused cognitive-behavioral therapies, involving the partner in the treatment process. Other sexological approaches could be useful. We recommend the use of dapoxetine as first-line, on-demand oral therapy for primary and acquired PE. We recommend the use of lidocaine 150mg/mL/prilocaine 50mg/mL spray as local treatment for primary PE. We suggest the combination of dapoxetine and lidocaine/prilocaine in patients insufficiently improved by monotherapy. In patients who have not responded to treatments with marketing authorisation, we suggest using an off-label SSRI, preferably paroxetine, in the absence of a contraindication. We recommend treating ED before PE in patients with both symptoms. We do not recommend using α-1 blockers or tramadol in patients with PE. We do not recommend routine posthectomy or penile frenulum surgery for PE.

CONCLUSION

These recommendations should contribute to improving the management of PE.

The Influence of Tramadol on Intravaginal Ejaculatory Latency Time and Sexual Satisfaction Score in Treating Patients With Premature Ejaculation: A Network Meta-Analysis

This network meta-analysis aimed at assessing the influence of tramadol on the intravaginal ejaculatory latency time (IELT) and sexual satisfaction score (SSS) in treating patients with premature ejaculation (PE). The PubMed, Embase, Cochrane Library databases (until July 2021), and original references of the included articles was systematically retrieved. The PRISMA checklist was followed. Finally, 14 articles including 1971 patients were included in this analysis. The results indicated that patients who were treated with tramadol (50 mg, 62 mg, 89 mg, and 100 mg) were superior to those treated with placebo in terms of IELT (p = .003, p < .00001, p < .00001, and p < .00001, respectively), but 25 mg tramadol did not show a significant advantage (p = .06). Patients who were treated with tramadol (50 mg and 100 mg) had a better efficacy than who were treated with 25 mg tramadol in the IELT (p < .00001 and p < .00001), but the effect of 50 mg tramadol and 100 mg tramadol were not significantly different (p = .17). The tramadol group had the better effect than the placebo group in the SSS (p < .0001). And 50 mg tramadol showed a significant improvement compared with 20 mg paroxetine, as assessed by the IELT (p = .03) and SSS (p = .03). Safety assessments including adverse events suggested that tramadol was well tolerated. Tramadol showed a better improvement of IELT and SSS than placebo or paroxetine, and 50 mg tramadol may be a more reasonable therapeutic dose for patients with PE.

Safety and efficacy of "on-demand" tramadol in patients with premature ejaculation: an updated meta-analysis

INTRODUCTION

Tramadol has been used for the treatment of premature ejaculation, however, the studies published for the same are not well designed. The primary objective of this study was to explore the literature pertaining to the use of tramadol in patients with PE to determine its safety and efficacy in this population. Materials ande methods: Systematic literature search of various electronic databases was conducted to include all the randomized studies and quasi-randomized studies. Standard PRISMA (Preferred reporting Items for Systematic reviews and Meta-analysis) guidelines were pursued for this review and study protocol was registered with PROSPERO (CRD42019123381).

RESULTS

Out of 9 studies included in this review, 5 were randomized controlled trials, and rests of the 4 studies were quasi-randomized studies. Tramadol resulted in significantly higher improvement of IELT with the mean difference (MD) of 139.6 seconds and confidence interval (CI) 106.5-172.6 seconds with a p-value of p < 0.00001. All dosages except 25mg fared well as compared to placebo. Tramadol fared better than placebo at 1 month, 2 months, and 3 months after initiation of therapy as compared to the placebo. Tramadol group had reported a significantly higher number of adverse events with treatment as compared to placebo but none of them were serious.

CONCLUSION

Tramadol appears to be an effective drug for the management of PE with a low propensity for serious adverse events. However, evidence obtained from this study is of low to moderate quality. Furthermore, effective dose and duration of therapy remain elusive.

Drosophila Corazonin Neurons as a Hub for Regulating Growth, Stress Responses, Ethanol-Related Behaviors, Copulation Persistence and Sexually Dimorphic Reward Pathways

The neuronal mechanisms by which complex behaviors are coordinated and timed often involve neuropeptidergic regulation of stress and reward pathways. Recent studies of the neuropeptide Corazonin (Crz), a homolog of the mammalian Gonadotrophin Releasing Hormone (GnRH), have suggested its crucial role in the regulation of growth, internal states and behavioral decision making. We focus this review on Crz neurons with the goal to (1) highlight the diverse roles of Crz neuron function, including mechanisms that may be independent of the Crz peptide, (2) emphasize current gaps in knowledge about Crz neuron functions, and (3) propose exciting ideas of novel research directions involving the use of Crz neurons. We describe the different developmental fates of distinct subsets of Crz neurons, including recent findings elucidating the molecular regulation of apoptosis. Crz regulates systemic growth, food intake, stress responses and homeostasis by interacting with the short Neuropeptide F (sNPF) and the steroid hormone ecdysone. Additionally, activation of Crz neurons is shown to be pleasurable by interacting with the Neuropeptide F (NPF) and regulates reward processes such as ejaculation and ethanol-related behaviors in a sexually dimorphic manner. Crz neurons are proposed to be a motivational switch regulating copulation duration using a CaMKII-dependent mechanism described as the first neuronal interval timer lasting longer than a few seconds. Lastly, we propose ideas to use Crz neuron-induced ejaculation to study the effects of fictive mating and sex addiction in flies, as well as to elucidate dimorphic molecular mechanisms underlying reward behaviors and feeding disorders.

Management of premature ejaculation: a clinical guideline from the Italian Society of Andrology and Sexual Medicine (SIAMS)

Premature ejaculation (PE) is the most prevalent male sexual dysfunction, and the most recently defined. PE is often mistakenly considered a purely psychosexological symptom by patients: the lacking awareness in regards to the pathophysiology and treatments often lead to resignation from the patients' side, making PE the most underdiagnosed sexual complaint. However, an ever-growing body of evidence supporting several organic factors has been developed in the last decades and several definitions have been suggested to encompass all defining features of PE. In the present document by the Italian Society of Andrology and Sexual Medicine (SIAMS), we propose 33 recommendations concerning the definition, pathophysiology, treatment and management of PE aimed to improve patient care. These evidence-based clinical guidelines provide the necessary up-to-date guidance in the context of PE secondary to organic and psychosexological conditions, such as prostate inflammation, endocrine disorders, and other sexual dysfunctions, and suggest how to associate pharmacotherapies and cognitive-behavioral therapy in a couple-centered approach. New therapeutic options, as well as combination and off-label treatments, are also described.

A Comparative Study of Yoga with Paroxetine for the Treatment of Premature Ejaculation: A Pilot Study

Context:

Premature ejaculation (PME) is a common sexual disorder. Drugs used commonly used for its treatment have various side effects and disadvantages. Yoga is being increasingly studied in a variety of medical disorders with positive results. However, its evidence for patients with PME is very limited.

Aims:

The aims of this study were to investigate the effect of yoga on ejaculation time in patients with PME and to compare it with paroxetine.

Settings and Design:

This was a nonrandomized nonblinded comparative study in a tertiary care center.

Materials and Methods:

Among patients with PME, 40 selected paroxetine and 28 yoga. Intravaginal ejaculation latency time (IELT) was measured in seconds once before and three times after intervention.

Statistical Analysis Used:

Mean, standard deviation, paired and unpaired t-tests, and repeated measures ANOVA were used for statistical analysis.

Results:

IELT was significantly increased in both groups – paroxetine (from 29.85 ± 11.9 to 82.19 ± 32.9) and yoga (from 25.88 ± 16.1 to 88697 + 26.9). Although the effect of yoga was slightly delayed in onset, its effect size (η² = 0.87, P < 0.05) was more than paroxetine (η² = 0.73, P < 0.05). One-fifth of the patients in the paroxetine group (19.5%) and 8% in the yoga group continued to have the problem of PME at the end of the trial.

Conclusions:

Yoga caused improvement in both intravaginal ejaculation latency time and subjective sexual experience with minimal side effect. Therefore, yoga could be an easily accessible economical nonpharmacological treatment option for the patient with PME.

Perceptions, Expectations, Preferences, and Attitudes Toward Premature Ejaculation, Its Diagnosis and Topical Treatment with Fortacin™ Spray: Results from an Expert Panel Discussion

INTRODUCTION

Premature ejaculation (PE) represents the most prevalent male sexual issue. Before beginning treatment, it is essential to discuss the patient's expectations thoroughly.

METHODS

Herein, we report the results of an expert panel discussion about perceptions, expectations, preferences, and attitudes towards PE, its diagnosis and treatment. The panel took place in October 2019 and involved 30 Italian urologists experienced in the management of male sexual dysfunction. It aimed at investigating physicians' points of view about selected aspects of PE management which emerged during the counselling of PE patients over the previous two years. Treatment-related questions were mainly focused on topical treatment with Fortacin™.

RESULTS

Overall, 83.3% of those interviewed declared that most of their patients perceive PE as a bother rather than a disease. The percentage of urologists interviewed perceived that improved subjective control over ejaculation and prolonged intravaginal ejaculatory latency time (IELT) as the main benefit expected by the majority of their patients was 56.5% and 10%, respectively. Eighty percent of urologists reported on-demand regimen as the dosage modality preferred by the majority of their patients and half of them reported the topical route to be the way of administration preferred in most cases. Moreover, 73.3% of urologists reported that adherence to treatment was higher in patients undergoing topical treatment. Finally, 80% of urologists perceived Fortacin to be efficacious in patients with acquired PE and 70% of them perceived its efficacy to be independent from IELT.

DISCUSSION

Most patients perceive PE as a bother rather than a disease and mainly advocate an improved control over ejaculation. Fortacin is perceived as efficacious in patients with acquired PE, and independent from IELT.

A Double Blind, Placebo Controlled, Randomized Trial to Evaluate the Efficacy and Tolerability of On-Demand Oral Pregablin (150 mg and 75 mg) in Treatment of Premature Ejaculation

INTRODUCTION

Although premature ejaculation (PE) is a common sexual dysfunction, the available options for PE treatment remain unsatisfactory.

AIM

To evaluate the effect of on-demand oral pregabalin on the intravaginal ejaculation latency time (IELT).

METHOD

We conducted a multiarm double-blinded placebo-controlled randomized clinical trial that enrolled 120 patients with PE who were divided equally into 3 groups (A, B, and C). 4 patients were excluded, 39 patients received 150 mg pregabalin (group A), 39 patients received 75 mg pregabalin (group B), and 38 patients received placebo (group C). All patients were encouraged to engage in sexual relations twice per week for 2 weeks and to take the medication 1-2 hours before sexual intercourse. A stopwatch was used to evaluate IELT.

MAIN OUTCOME MEASURE

The main outcome measure are the improvement of IELT and the reported adverse events.

RESULTS

IELT significantly improved in patients who received 150 mg pregabalin, but there was no change in the other groups.

CLINICAL IMPLICATIONS

Most PE patients showed a significant improvement after receiving on-demand pregabalin (150 mg).

STRENGTH & LIMITATIONS

The strength of this study is that it is the first randomized controlled trial to evaluate the efficacy of pregabalin in treatment of PE. The main limitations were the small number of patients, IELT was the only primary outcome of the study, and the pregabalin cap can be identified by the patient.

CONCLUSION

Oral pregabalin seems to be a promising drug for additional evaluation as a new treatment for PE. More studies are needed to evaluate the suitable dose, duration, timing, and its safety profile. El Najjar MR, El Hariri M, Ramadan A, et al. A Double Blind, Placebo Controlled, Randomized Trial to Evaluate the Efficacy and Tolerability of On-Demand Oral Pregablin (150 mg and 75 mg) in Treatment of Premature Ejaculation. J Sex Med 2020;17:442-446.

Premature ejaculation: challenging new and the old concepts

Premature ejaculation remains a difficult condition to manage for patients, their partners, and the clinician. Whilst prevalence rates are estimated to be 20-40%, determining a diagnosis of premature ejaculation is difficult, as the definition remains both subjective and ill-defined in the clinical context. As our understanding of the ejaculatory pathway has improved, new opportunities to treat the condition have evolved with mixed results. In this review, we explore some of these controversies surrounding the aetiology, diagnosis, and treatment of this condition and discuss potential novel therapeutic options.

Administration of an oxytocin receptor antagonist attenuates sexual motivation in male rats

In male rats, oxytocin impacts both sexual arousal and certain types of consummatory sexual behaviors. However, the role of oxytocin in the motivational aspects of sexual behavior has received limited attention. Given the role that oxytocin signaling plays in consummatory sexual behaviors, it was hypothesized that pharmacological attenuation of oxytocin signaling would reduce sexual motivation in male rats. Sexually experienced Long-Evans male rats were administered either an oxytocin receptor antagonist (L368,899 hydrochloride; 1mg/kg) or vehicle control into the intraperitoneal cavity 40min prior to placement into the center chamber of a three-chambered arena designed to assess sexual motivation. During the 20-minute test, a sexually experienced stimulus male rat and a sexually receptive stimulus female rat were separately confined to smaller chambers that were attached to the larger end chambers of the arena. However, physical contact between test and stimulus rats was prevented by perforated dividers. Immediately following the sexual motivation test, test male rats were placed with a sexually receptive female to examine consummatory sexual behaviors. Although both drug and vehicle treated rats exhibited a preference for the female, treatment with an oxytocin receptor antagonist decreased the amount of time spent with the female. There were no differences between drug and vehicle treated rats in either general activity, exploratory behaviors, the amount of time spent near the stimulus male rat, or consummatory sexual behaviors. Extending previous findings, these results indicate that oxytocin receptors are involved in sexual motivation in male rats.

Comparison of the clinical efficacy and safety of the on-demand use of paroxetine, dapoxetine, sildenafil and combined dapoxetine with sildenafil in treatment of patients with premature ejaculation: A randomised placebo-controlled clinical trial

The aim of the study was to compare the clinical efficacy and safety of the on-demand use of paroxetine, dapoxetine, sildenafil and combined dapoxetine with sildenafil in treatment of patients with premature ejaculation (PE). In a single-blind placebo-controlled clinical study, 150 PE patients without erectile dysfunction (ED) were included during the period of March 2015 to May 2016. Patients were randomly divided into five groups (30 patients each). On demand placebo, paroxetine (30 mg), dapoxetine (30 mg), sildenafil citrate (50 mg) and combined dapoxetine (30 mg) with sildenafil citrate (50 mg) were given for patients for 6 weeks in each group respectively. All patients were instructed to record intravaginal ejaculatory latency time (IELT) and evaluated with Premature Ejaculation Diagnostic Tool (PEDT) and the patient satisfaction score before and after treatment. The mean of IELT, satisfaction score and PEDT in all groups was significantly improved after treatment (p value = .001). Combined dapoxetine with sildenafil group had the best values of IELT, satisfaction scores and PEDT in comparison with other treatment groups (p value <.001). The combined dapoxetine with sildenafil therapy could significantly improve PE patients without ED as compared to paroxetine alone or dapoxetine alone or sildenafil alone with tolerated adverse effects.

Lidocaine/prilocaine spray for premature ejaculation

Although premature ejaculation is the most common ejaculation problem, it is poorly understood and currently has no standard definition.¹ Typically, it involves reduced time to ejaculation, inability to control or delay ejaculation and associated distress.^1-5 Treatments that have been assessed include psychosexual counselling, antidepressants (e.g. selective serotonin reuptake inhibitors), phosphodiesterase type-5 inhibitors, tramadol and topical anaesthetic agents (e.g. lidocaine/prilocaine cream). A new formulation (cutaneous spray) of lidocaine/prilocaine (Fortacin-Plethora Solutions Ltd.) was launched in the UK in November 2016 for the treatment of primary premature ejaculation.^6,7 Here, we consider the evidence for lidocaine/prilocaine spray and whether it has a role in the treatment of premature ejaculation.